Current brief tests of cognitive functioning have poor psychometric properties and inconsistent predictive values. The objective of this proposal is to develop a test of cognition to be administered over the telephone, specifically for the purpose of detecting age-related cognitive change. This test will be based on the existing Telephone Interview of Cognitive Status- Modified. Using preliminary analyses from a sample of 3,681 women over 75 years of age, we present information on the domains that are effectively assessed by the TICSm. Based on a review of the theoretical and empirical understanding of the nature of age- related cognitive change, we propose to incorporate additional items to assess current domains. Further we will generate items to evaluate processing speed, working memory, executive functioning and to expand the assessment of explicit verbal memory. The goal is to produce a reliable and valid test of cognition that effectively assesses domains most impacted by age. The approach to developing this instrument will rely on classical psychometric theory. Specific aims are: 1) To develop an enhanced computer assisted version of the TICSm. This new instrument will evaluate cognitive domains currently assessed by the TICSm and additionally the domains of verbal learning, perceptual speed, executive functioning and working memory. We will include a speech and tone discrimination task to assure telephone testing is appropriate. 2) To validate the enhanced TICSm. This will be done by administering a battery of standardized in-person tests that evaluate a range of cognitive domains. 3) To provide normative information on a population based sample of individuals over the age of 65 and to evaluate the nature of the practice effect. We will recruit a sample of 50 individuals over 65 in a study designed to generate items, and a sample of 100 to select effective items for the new instrument. We will then recruit a separate sample of 300 individuals who will take the new instrument and a battery of standard neuropsychological and hearing tests to validate the new instrument. Finally, we will recruit a sample of 1,000 older adults to provide normative data. This three-year study will provide the first brief test of cognitive domains, impacted by age, developed according to established psychometric criteria.